Hoffman Steam Air Vent 401422 1A, 1/8" Adjustable Angle Steam Radiator Air Valve Air valve (non-vacuum) float-type vent Adjustable port for true proportional venting v 6 port settings from slow (1) to fast (6 1/8" npt angle connection maximum operating pressure 1 1/2 psig (0.1 bar) Air Valve (non-vacuum) Float-type vent Adjustable port for true proportional venting v 6 port settings from slow (1) to fast (6) 1/8" NPT angle connection Maximum operating pressure 1 1/2 psig (0.1 bar)